This invention is in the technical field of exercise equipment; more particularly the exercise equipment known as selectorized equipment. The present invention relates to resistance training of skeletal muscles utilizing resistance training equipment consisting of a plurality of equal thickness weights plates arranged vertically using guides and a selector shaft with openings or slots corresponding to weight plate slots able to accept an intersecting pin shaft to secure a selection, commonly known in the fitness industry as “selectorized” equipment.
As skeletal muscles are introduced to greater external loads, such as resistance training, they initially are capable of providing the necessary force but only for a few cycles of motion relative to the load applied until the point of momentary muscle failure. At this point the load is too great for the available muscle fibers to concentrically contract but if the load could be quickly reduced, the same movement could be continued immediately, virtually seamlessly with the same perceived effort to the trainee resulting in more complete muscle fiber stimulation and ultimately greater results.
The equipment known as selectorized equipment introduced decades ago and continuously refined was a great improvement over the barbell in terms of safety, user friendliness and acceptance especially among persons intimidated by free weight usage. For all the advantages and refinement selectorized equipment has over it's free weight counterpart one obvious similarity is: the initial resistance chosen by the trainee will remain static from the beginning of the movement to the point of momentary muscular failure. I.E. One hundred pounds of resistance selected before the commencement of the movement remains one hundred pounds during and at the termination of the movement, unless acted upon by external forces. Momentary muscular failure is the absolute termination point of any resistance exercise if not acted upon by external forces. An assistant could provide assistance with additional movement effectively reducing the load experienced by the trainee or the trainee could cease the movement, adjust the selection of resistance then continue. Both scenarios will further enable the trainee to progress but are not ideal as the former requires additional personnel and a rest period, the later requires the trainee to stop, dismount, adjust the selection, remount then continue the movement resulting in a greater rest period, which is counterproductive but the only options available up to this point by the fitness industry.
Other types of resistance equipment not known to the industry as selectorized equipment may provide the benefits of variable, descending resistance during the movement but consist of equipment outside the manufacture and construction of selectorized resistance equipment. These may be pneumatic, hydraulic, and electronic or any combination of but relies on substantially dissimilar technology to apply and vary resistance and are incompatible with claims made in this specification.
The common method of ejecting a pin from a selection slot is a coiled biasing means, a spring, of sufficient power able to eject the shaft from the selection. An assistant can place a suitably sized coiled spring over a standard selector pin shaft, insert into desired selection of a selectorized weight stack, compress the spring by inserting the shaft fully into the selection and hold it stationary until the trainee commences the movement at which point the assistant can be relieved of this duty. Once the weight stack is returned to the resting position, the pin shaft will eject. The existing problem remains the release methods claimed.
U.S. Pat. No. 4,610,449 describe an automatic weight stack selector for exercise equipment employing a timer, and assorted equipment to change weight after a predetermined amount of time. The apparatus described is not portable to a trainee and relies on a timer mechanism with a pre-set time frame to actuate without regard to the trainee's load requirement at any given instant of an exercise.
U.S. Pat. No. 5,556,362 describes a weight stack pin biased by a spring of various material and construction that relies on a specific weight stack construction method and material used in manufacture to achieve the desired function of retaining and or release upon command of the trainee. In drawings and descriptions it describes and shows the units consecutively arranged in selectorized weight stacks without the need to skip a selection to allow any portion of a trigger mechanism to enter any unoccupied selection slots. It describes various methods in the attempt of reliable function of the unit but in practice of construction of the described claims it became apparent of the dissimilarity of the claims to the present invention claim.
Patent Application Publication 2011/0091272A1 describes weight stack pin biased by a spring with a trigger catch. Further description of claimed function describes the engagement and release of unit from a weight stack. “Lifting of the stack plates so as to engage the pop-pin against the stack of weight plates and shock the spring from the unstable equilibrium point to set the loaded spring against the weight stack” This description of claimed function of release by shock is arbitrary and as such would not allow reliable, repeatable function or multiple units to be used during a single exercise.
None of the above references claim, either separately or combined the operation of the following claim of operation of the invention.